Unexpected data in swap partition

RAM 8 GB, swappiness 1.

I updated from digiKam 4 to digiKam 5 and set up the database of my photos from scratch (about 40 MB). RAM usage went up to 3.2 GiB (I had expected more). At the same time my swap partition got 880 kiB, not that much for sure. But why is there any data at all with such a lot of RAM unused?


You don’t normally see “peak” RAM usage, if during your DB rebuild total RAM allocation (not necessarily actual use) went near 8GB the kernel might have swapped some unused buffers to be on the safe side.
Also, having a swap available the kernel makes only a rough estimate of the RAM needed by an application and might resort to swap in case it temporarily exceeds that.
For a detailed answer, an expert in kernel memory management is needed (sorry, that’s beyond my pay grade :wink: ).

Thank you. This gives me a glimpse of the processes behind the curtain.